PH and concentration meter



FIG. 1 is an isometric view from the front of a pH and concentration meter incorporating our design;

FIG. 2 is a left side view thereof;

FIG. 3 is a bottom view thereof;

FIG. 4 is a right side view thereof;

FIG. 5 is a front view thereof; and,

FIG. 6 is a back view thereof. 

The ornamental design for a pH and concentration meter, as shown and described. 